An Omnidirectional Microrobot with Micro Cilia
Yu-Ming Chen, Anshuman Shukla, Eric Black, Matt Mohebbi, M. Terry, Joel
Reiter, R. Bruce Darling, Karl F. Böhringer
John W. Suh, Greg Kovacs (Stanford)
An omnidirectional mobile microrobot realized by microelectromechanical
system (MEMS) actuator arrays is presented. The microrobot consists of two
rigidly connected microcilia array chips, each having an 8x8 array of "motion
pixels," which are composed of four orthogonally oriented thermal bimorph
actuators. This allows for reliable, accurate motion in three degrees of
freedom (x;y;theta) in the plane, a first for a microrobot of this kind.
The microrobot is approximately 3cm in length, 1cm in width, 1mm in height,
and has a mass of less than half a gram. By varying the input power, actuation
frequency and motion gait strategy the velocity of the chip can be precisely
controlled. Motion in three degrees of freedom has been demonstrated and
a maximum velocity of 635 µm/s and carrying capacity greater than
1.448 g (two 8-pin ICs) has been observed. The microrobot has been characterized
extensively and a model for its performance is described.
|Figure 1: Microrobot in relation
to a US Dime. Note the two (dark) cilia chips bonded to the PCB board.
Wire bonds on the bottom side connect the 5 channels of each chip
to pads on the PCB board. Nine wires (two sets of four directions
plus a common ground) soldered to the top side pads connect the robot
to the controller.
||Figure 2: Northwest motion translational
displacements. Plots represent, from bottom up, 30, 60, 120 and 90Hz
control frequencies. The highest velocity for these frequencies is
achieved at 90Hz.
- Yu-Ming Chen, John W. Suh, Gregory T. A. Kovacs, R. Bruce Darling,
Karl F. Böhringer, "Modeling and Control of a 3-Degree-of-Freedom
Walking Microrobot," Hilton Head 2006: A Solid State Sensor, Actuator,
and Microsystems Workshop, Hilton Head Island, NC, June 4-6, 2006.
- Yu-Ming Chen, "Thermal Model of a Microrobot", M.S.
thesis, University of Washington, Seattle, WA, December 2005.
- Matthew H. Mohebbi, M. L. Terry, Karl F. Böhringer, John W. Suh,
Gregory T. A. Kovacs, "Omnidirectional Walking Microrobot Using MEMS
Thermal Cilia Arrays." ASME International Mechanical Engineering
Congress and Exposition (IMECE'01), no. 23824, New York, NY, November
11-16, 2001. Paper.
A complete list of our publications
(many of them available online) can be found here.
- NSF CAREER award ECS- 9875367 (REU supplement)
- AFRL prime contract F29601-98-D-0210, USRA subcontract 9500-20
- DARPA contract N001-92-J-1940-P00001, a General Motors Key grant
and NSF NYI award ECS-9358289-006 to G. Kovacs (chip fabrication)
© Karl F. Böhringer, Department of Electrical Engineering, Box
352500, Seattle, WA 98195-2500, USA